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    <title>ShellCheck: SC2284 – Use `[ x = y ]` to compare values (or quote `'=='` if literal).</title>
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    <h1>SC2284 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2284">See this page on GitHub</a>
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    <h2 id="use--x--y--to-compare-values-or-quote--if-literal">Use
<code>[ x = y ]</code> to compare values (or quote <code>'=='</code> if
literal).</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2284.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="cf">if</span> <span class="va">$var</span> == value</span>
<span id="cb1-2"><a href="SC2284.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="cf">then</span></span>
<span id="cb1-3"><a href="SC2284.html#cb1-3" aria-hidden="true" tabindex="-1"></a>  <span class="bu">echo</span> <span class="st">&quot;Match&quot;</span></span>
<span id="cb1-4"><a href="SC2284.html#cb1-4" aria-hidden="true" tabindex="-1"></a><span class="cf">fi</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2284.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="cf">if</span> <span class="bu">[</span> <span class="st">&quot;</span><span class="va">$var</span><span class="st">&quot;</span> <span class="ot">=</span> value <span class="bu">]</span></span>
<span id="cb2-2"><a href="SC2284.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">then</span></span>
<span id="cb2-3"><a href="SC2284.html#cb2-3" aria-hidden="true" tabindex="-1"></a>  <span class="bu">echo</span> <span class="st">&quot;Match&quot;</span></span>
<span id="cb2-4"><a href="SC2284.html#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">fi</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>ShellCheck found an unquoted <code>==</code> after a word.</p>
<p>This was most likely supposed to be a comparison, so use square
brackets as in the correct code.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>If the <code>==</code> was supposed to be literal, you can quote it
to make ShellCheck ignore it:</p>
<pre><code>grep &#39;===&#39; file.js</code></pre>
<h3 id="related-resources">Related resources:</h3>
<ul>
<li>Help by adding links to BashFAQ, StackOverflow, man pages, POSIX,
etc!</li>
</ul>
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